Illinois Crop Improvement Association, Inc. | Seed Lab

The following is a list of the more common tests conducted at Illinois Crop Improvement Association, Inc. Each test listed includes a brief description. If you would like a more detailed procedure, please give us a call at 217.359.4053 or e-mail us. E-mail information is listed in the Contact Us section.

	Standard Germination (Warm Germ) A standard germination is performed in our laboratory by recognized methodologies (AOSA, ISTA, FSA, Canadian rules, and other methodologies). In the absence of recommended methodologies for some crops, ICIA protocols will be used. Standard germination media used by ICIA are creped cellulose paper (CCP known as Kimpak), roll towel, blotter, CCP with a layer of sand, and CCP with a layer of soil.
A standard germination is designed to give the seed the best opportunity to develop into a healthy seedling. The seed is placed in an environment, which will subject the seed/seedling to as little stress as possible. At the end of the prescribed germination time, the seedlings are evaluated by our team of seed analysts.
Varietal Purity (Visually Detectable Characteristics) The varietal purity test is primarily a visual test by our highly trained seed analysts using physical characteristics of the seed to distinguish between different varieties of the same crop kind. For instance, the analysis on a soybean sample is based on hilum color, hilum shape, seed coat color, and seed coat luster. Oat varietal purities are based on the fluorescence test. Other tests used are phenol test and sodium hydroxide test for wheat; peroxidase test and hypocotyl color test for soybeans. Other varietal tests that are widely recognized as useful in determining a variety are available upon request.
Physical Purity (Mechanical Purity) All purities are conducted by prescribed methodologies (AOSA, ISTA, USDA, or CFIA). Weights used are based on required amounts from these methodologies. The working sample is broken down into the specified components: pure seed, weed seed, other crop seed, broken seed, and other inert matter. Percentages of each are reported along with a detailed listing of each component and/or noxious weeds found.
Cold Test A cold test is a stress test based on subjecting the imbibed seed to adverse conditions based on temperature, high moisture level, and soil borne pathogens, in order to determine the vigor level of the seed lot. Seedlings are evaluated for abnormalities at the end of a cold/warm cycle. This test is available for corn, soybeans, sorghum, etc.
Seed Count Test The seed count test is a machine measurement of the seeds per pound of any crop kind. AOSA rules are used, where applicable, for several different crops. For crops without published methodologies, sample weights for similar size seeds are used. Seed counts are necessary to determine planting populations.
Accelerated Aging Test (AA Test) The AA test is a stress test based on subjecting the seed to conditions based on high temperatures and a high moisture level. The accelerated aging test is used as a vigor test for a wide variety of crops and may also be used to determine storability of seed.
Conductivity Test The conductivity test is a biochemical test, which measures the amount of electrolytes, which leach through the seed coat or fruit coat of the intact seed. A higher conductivity may indicate a low vigor seed lot. The expected readings for a conductivity test will vary greatly from crop to crop. It is most useful for peas, soybean samples, and a lesser degree for corn.
Tetrazolium Test (TZ) The TZ test is a quick test used to estimate the germination potential of seed (seed viability), but it may also be used as a trouble shooting diagnostic tool. It may be used effectively to detect mechanical damage in legume seeds and dead tissue in all species.
Seed Coat Damage Test (Hypochlorite Test) The seed coat damage test is used to detect soybean seed coat damage. It is designed for use during harvest, but may be extremely useful in detecting problem areas in a handling and conditioning system.
Fast Green Test (Pericarp Damage) The fast green test is a quick test used to detect pericarp (seed coat) damage in seed corn. It may also be used on other cereal crops such as wheat and grain sorghum. In addition, suspected damaged seeds may then be run through the germination process to determine how the pericarp damage is related to germination problems.

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